As an assembled battery (battery module) including a plurality of stacked electric storage devices with a spacer interposed therebetween, there is known an electric storage apparatus that includes an insulation frame such as a spacer arranged on an electric storage device.
In such an electric storage apparatus, the insulation frame generally includes a main plate portion which is arranged on the electric storage device and a plurality of flange portions which are provided on a peripheral portion of the main plate portion. Each flange portion is arranged so as to be opposed to an outer peripheral surface of the electric storage device. The electric storage device is positioned by the flange portions.
JP 2013-004341 A discloses a structure in which ribs project from a main plate portion of an insulation frame and extend in a lateral direction. In a state where an electric storage device and the main plate portion of the insulation frame are alternately stacked, the ribs are sandwiched between the main plate portion and the electric storage device and resiliently deformed to be bent. Such a structure can prevent movements or rattling of the electric storage device, which is sandwiched between the main plates, in a direction orthogonal to the main plate.
Conventional electric storage apparatuses including the one disclosed in JP 2013-004341 A had not particularly considered to suppress rattling of an electric storage device in a direction parallel to a main plate portion of an insulation frame.